A washing machine is an apparatus that eliminates foreign substances in and/or attached to laundry by agitating and rotating water, detergent, and the laundry. Washing machines may be classified into a pulsator type washing machine that washes the laundry using a water flow generated by a pulsator in the washing tub, and a drum type washing machine that washes laundry by dropping the laundry vertically as a result of rotation of the drum.
The drum type washing machine has a door that is at the front of the washing machine. The user puts the laundry in the washing machine through the door, and the drum type washing machine lifts and drops the laundry to wash the laundry, using relatively small amounts of water and detergent. Specifically, a drum type washing machine in the related art includes a cabinet that forms an external appearance and/or structure of the washing machine, a tub that is in the cabinet and stores water, a rotatable drum that is in the tub and holds or accommodates laundry, a drive motor that is behind and/or below the tub and provides power to the drum, a water supply device (e.g., a pump and/or valve) that supplies water to the tub, and a drain that discharges water in the tub to the outside of the cabinet after a washing operation ends.
Accordingly, when the laundry is washed using the drum type washing machine in the related art, the laundry is put into the tub laterally by opening the door at the front of the washing machine, water is supplied to the tub, and then the laundry is washed while a lifter in the drum lifts up and drops the laundry by rotating the drum using power from the drive motor.
As such, the drum type washing machine in the related art includes a separate tub in addition to the drum. That is, the drum type washing machine in the related art has a structure that includes the tub to store water and the drum in the tub to wash the laundry.
However, because the tub is typically made of a plastic material, the tub may be easily contaminated by mold, mildew, water scale or other foreign substances entering or generated in the tub when the tub is used over a long period of time. There is a problem in that it is difficult to clean the tub when the tub is contaminated because the drum must be removed first. When the tub is contaminated, the tub may become corroded or contaminated, and then the laundry may become contaminated, which may cause a user to incur skin irritation or a skin disease.
This problem also exists in the pulsator type washing machine as well as the drum type washing machine. The reason is that the pulsator type washing machine also includes a reservoir (tub) in a main body thereof.
According to the drum type washing machine in the related art, the drum rotates by supporting one side of the drum using a single shaft, and thus, there is also a problem in that vibration(s) and noise may occur due to deflection(s) of the shaft.